The present invention relates to an inhalation device for use in the administration of medicament to a patient. The device has a mouthpiece, which is reversibly retractable from a storage position located inside the body of the device to a dispensing position in which the mouthpiece protrudes from the body of the device.
The use of inhalation devices in the administration of medicaments, for example in bronchodilation therapy, is well known. Such devices generally comprise a body or housing within which a medicament container is located. A mouthpiece (or nozzle) is typically provided, wherein xe2x80x98in usexe2x80x99 the mouthpiece communicates with the medicament container to allow passage of medicament from the source to the mouthpiece and thence, to the patient.
In a typical dispensing operation the body of the device is held by the patient and the mouthpiece (or nozzle) of the inhalation device is placed in the mouth (or nose) of the patient. The patient inhales, thereby causing transfer of medicament from the medicament container to the interior of the body of the patient.
When not in use it is desirable, from a hygiene standpoint, that the mouthpiece is provided with some kind of protective cover. The cover desirably acts both to prevent build-up of dirt on the mouthpiece and to prevent ingress of dirt into the body of the device through the mouthpiece, which might then be subject to inhalation by a patient.
It is known to provide the mouthpiece with a protective cap which acts as a protective cover. The cap may either be an entirely separate element or it may be joined to the body of the device in some way. DE-A-3,639,836, for example, describes a device in which the protective cap is mounted on an arm, which is pivotally mounted to the body of the device.
As an alternative to the use of a protective cap, one might envisage a device having a mouthpiece which is reversibly retractable from a storage position in which the mouthpiece is contained within the body of the device to a dispensing position in which the mouthpiece protrudes from the body of the device. In a device of this type the body of the device itself acts as the protective cover when the mouthpiece is in the storage position. The mouthpiece cover is thus an integral part of inhalation device, avoiding contamination problems of prior art inhalation devices caused by loss of removable mouthpiece covers.
GB-A-2,074,454 describes an inhalation device comprising a tubular body adapted for detachable fitting to an aerosol container. A mouthpiece is provided, which is movable from a storage position to a dispensing position by means of rotation of a cap, which is mounted on the tubular body. The cap and tubular body are provided with openings of similar dimensions. Manual rotation of the cap to bring the openings into register causes the mouthpiece to be moved to the dispensing position in which the mouthpiece protrudes from an opening provided in the cap. Conversely, rotation of the cap by the user to bring the openings out of register causes the mouthpiece to be moved to the storage position in which the mouthpiece is contained within the body of the device.
For efficiency, it is desirable that the manual action of the user, which initiates the mouthpiece actuation does not interfere with the movement of the mouthpiece from the storage to dispensing position (and vice-versa). It is particularly desirable, from a hygiene standpoint, that the mouthpiece does not come into contact with the hands of the user during the mouthpiece actuation process.
The device described in GB-A-2,074,454 requires manual rotation of the cap to move the mouthpiece to the dispensing position in which the mouthpiece protrudes from an opening provided in the cap. It is highly likely that in performing such manual rotation the patient""s hands will come into contact with the mouthpiece, thereby either inhibiting its movement or allowing for transfer of dirt or germs from the patient""s hands to the mouthpiece.
The Applicants have now devised a device having a mouthpiece which is reversibly retractable from a storage position to an in-use position by manual rotatory action of the patient in an efficient and hygienic manner, thereby overcoming the problems associated with the device of GB-A-2,074,454. It is a requirement of this device that the translational path definable by the movement of the mouthpiece from the storage to the in-use position does not bisect the rotational path defined by the rotation of the mouthpiece actuator.
According to one aspect of the present invention there is provided an inhalation device for dispensing medicament comprising
a body;
a medicament carrier;
a mouthpiece, reversibly movable from a storage position wherein said mouthpiece is within said body to an in-use position wherein a portion of the mouthpiece protrudes from the body and wherein the mouthpiece is in communication with said medicament carrier to allow passage of medicament therebetween; and
a mouthpiece actuator, rotatable relative to the body, and coupled to the mouthpiece such a first rotation of said mouthpiece actuator moves the mouthpiece towards said storage position and an opposing rotation of the mouthpiece actuator moves the mouthpiece towards said in-use position,
characterised in that the translational path definable by the movement of the mouthpiece from the storage to the in-use position does not bisect the rotational path defined by the rotation of the mouthpiece actuator.
Herein the term xe2x80x98mouthpiecexe2x80x99 is used in a generic sense to mean an element shaped such as to be insertable into the mouth or nose of a patient for inhalation therethrough.
In one preferred aspect, the mouthpiece actuator and mouthpiece are coupled by a coupling mechanism. In one particularly preferred aspect, the coupling mechanism comprises a rack and pinion mechanism. In another particularly preferred aspect, the coupling mechanism comprises a hinged lever mechanism.
In another preferred aspect, the mouthpiece actuator and mouthpiece are directly coupled.
In one aspect, the medicament carrier is within the body. In another aspect, the medicament carrier is attachable to the exterior of the body.
Preferably, the mouthpiece is comprised of an elastic material.
Preferably, the mouthpiece is provided with a cover comprised of an elastic material.
Preferably, the inhalation device additionally comprises a curtain arrangement contactable by the mouthpiece on movement of the mouthpiece from the storage to the in-use position. More preferably, the curtain arrangement comprises a plurality of curtains comprised of an elastomeric material.
Preferably, the mouthpiece actuator is provided with a safety trigger mechanism to prevent accidental actuation thereof.
Preferably, at least a portion of the mouthpiece actuator is shaped for ease of grip by the user.
Preferably, at least a portion of the mouthpiece actuator has a friction-enhancing coating.
Preferably, the device is provided with a dose counter, which indicates the number of doses dispensed from or remaining in the container. More preferably, the dose counter comprises an indexing mechanism actuated by a predetermined movement of the medicament container relative to the body.
Preferably the mouthpiece is actuable by a sliding thumb motion.
Preferably, the medicament container is an aerosol or a dry-powder container.
Preferably the mouthpiece actuator is actuable by one-handed operation.
According to another aspect of the present invention, there is provided the use of an inhalation device provided herein for dispensing medicament.